Body condition, not just the number on the scale
Vets judge a cat's weight with a 9-point body condition score (BCS) based on how easily you can feel the ribs and whether there is a waist. It works across breeds and frames, where a single "ideal weight" does not. A score of 4–5 out of 9 is the target.
| BCS (of 9) | What you feel | Status |
|---|---|---|
| 1–3 | Ribs, spine and hips obvious; no fat | Underweight |
| 4–5 | Ribs felt easily, visible waist, slight tummy tuck | Ideal |
| 6–7 | Ribs hard to feel, waist fading, rounded belly | Overweight |
| 8–9 | Ribs buried, no waist, fat pad on belly | Obese |
Turning a score into a target weight
Each point above 5 on the BCS is roughly 10% over ideal weight. A 6 kg cat scoring 7/9 is about 20% overweight, so a healthy target is near 5 kg. It is an estimate to aim at, not a precise prescription; your vet sets the real goal based on frame and breed.
Why weight matters, and what trips people up
- It is common. Roughly half of house cats are overweight, so a heavier cat can look normal simply because we are used to it.
- Breed changes the target. Maine Coons, Ragdolls and Bengals are healthy at higher weights; slim breeds like Siamese sit lower.
- Diet type counts. Wet food is generally lower in calories per gram than dry, and cats fed only dry food tend to drift heavier.
- Extra weight costs years. Cats kept at a healthy weight live noticeably longer with fewer joint, diabetes and heart problems.
Common questions
What is a healthy weight for a house cat?
Most domestic cats sit between about 3.5 and 5.5 kg (8 to 12 lb), but the right number depends on frame. Large breeds like Maine Coons run heavier at a healthy weight, so body condition matters more than a single target figure.
How do I know if my cat is overweight without a scale?
Use the body condition score. You should be able to feel the ribs with light pressure, see a visible waist from above, and see a slight tummy tuck from the side. If the ribs are hard to feel and there is no waist, the cat is carrying extra weight.
How fast should an overweight cat lose weight?
Slowly. Aim for roughly 0.5 to 1 percent of body weight per week under a vet plan. Rapid weight loss in cats can trigger a dangerous liver condition called hepatic lipidosis, so never crash-diet a cat.
